Decker, 30, joked that she resembled Swift's scary graveyard look, which is featured in the first minute.
"Guys. I look just like zombie Taylor Swift," the Grace and Frankie star captioned a screenshot of the singer, 27, crawling on the ground.
She added to a commenter: "I don't currently have any photos of me clawing my way out of the grave, but I'm going to work on it!"
MTV exclusively debuted Swift's latest music video during the star-studded show. The video appeared to make several references to fellow stars, including Kim Kardashian, Kanye West and her ex-boyfriends Tom Hiddleston and Calvin Harris.
The "Shake It Off" singer previously dropped the lyric video on Friday — and broke a record while doing so. It received more than 19 million views on YouTube in just 24 hours, surpassing The Chainsmokers' lyric video for "Something Like This" featuring Coldplay, which gained 9 million views in one day.
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